Timed dump bailer



Dec. 27, 1938.

INVENTOR GEORGE H E NN/S ATTORNEY 2 Sheets-Sheet l G. -H .ENNIS TIMEDDUMP BAILER Original Filed Sept. l5, 1935 Dec. 27, 1938. G. H. ENNIS2,141,179

' TIMED DUMP BAILER Original Filed Sept. 13, 1935 2 Sheets-'Sheet 2NVENTOR G50/wf H. EN/v/s Afro@ NE Y Patented Dee. 21, 193e UNITED STATESTIMED DUMP BAILER.

George H. Ennis, Long Beach, Calif.. assigner of one-half to Robert V.FunkJionx Beach, Calif.

Application september 1a, 1935, seem 10.50.431 aenewea Meren 419, ma

y 12 Claims. My invention relates to an apparatus whereby a dose orquantity of material4 may be deposited in a well or bore hole. Myinvention is of utility in the various arts, but it is'of` particularvalue in 5 thel oil producing industry and may be used to a very markedadvantage for depositing electrolyte in a well in order to prepare thewell for testing as covered by my patent entitled Method and apparatusfor determining the location of water l0 strata iniwells, No. 1,786,196,issued December 23,

I believe my invention to be broadly new not only in its entirety butalso in thev several sub- .combinations and the various novel elementswhich I have invented. In order to illustrate the principle andtheadvantages and features -of my invention, I will describe and disclosehereinafter certain forms of my invention, and I Will describe its usein connection with the depositing of eiec- 2 trelyte in en 011 wen. Itshould be understood, however, that my invention is not to be limited tothe precise details oi' construction which I have chosen to discloseherein nor to the particular use which I shall refer to.

In my patent referred to above I have disclosed a method of determiningthe point or points at which water enters a Well.` In order to make atest, as pointed out in my prior patent, it is only necessary to depositthe electrolyte at those points Where the water leakage occurred. Thispoint of entrance of the water may be at any lpoint in the well rangingfrom the extreme bottom of the well to the upper regions thereof. The

process referred to involves the depositing of an is not necessary toplace electrolyte in any other 40 part of the Well. It will be seen,therefore, that it is highly desirable to have a device which is capableof depositing or delivering electrolyte to the well at the precisedesired point where the test is to be made regardless of whether thislocation is at the bottom of the well or at any other elevation. In viewof the fact that I could not find a satisfactory device in the prior artI invented the apparatus which consitutes the subject matter of mypresent invention. It is an object of my invention to provide anapparatus for delivering a dose or charge of materialinto the well asany point from the bottom of the well to the upper regions thereof.

It is a further object of my invention to provide an apparatus of thecharacter mentioned in whichthe releasing oi the material or thedelivery oi' the material from the apparatus into the well is entirelyindependent of the walls of the well or any relative movement betweenthe apparatus and the walls of the well or the bottom thereof.

' It is another object of my invention to provide an apparatus of thecharacter referred to in which the charge is automatically released fromthe apparatus and delivered into the well. 10

It is a still further object of my invention to provide an apparatus ofthe general character referred to heretofore in which the materialisdischarged after a predetermined period of time.

' It isanother object .of my invention to provide 15 an apparatus of thegeneral character referred to in which the valve which is operable todischarge the material from the apparatus into the well is automaticallyopened upon the lapse of a predetermined period of time.

An additional object of my invention is to provide an apparatus of thegeneral character referred to having a time control means which may beset to open the discharge valve of the apparatus upon the lapse of anypredetermined period of time.

It is another object of my invention to provide an apparatus of thecharacter referred to in the preceding paragraph in which the time meansis set While the apparatus is at the surface of the ground and in whichthe time means operatesl an electrical means which in turn opens thedischarge valve of the apparatus. y

It is a still further object of my present invention to provide anapparatus of the Acharacter defined in the second preceding paragraph inwhich the time means is a hydraulic apparatus which is set at thesurface of the ground, and which after a predetermined period of timeoperates mechanism for opening the discharge valve of the apparatus.

A'still further object of my invention is to provide an apparatus of thegeneral character referred to heretofore in which the discharge valve isheid in closed position by apparatusy which may be operated from thesurface of the ground at any desired time, and which is operatedentirely independent of the walls of the well or any relative movement`between the apparatus and the Well.

In the detailed description of different forms of my invention which isto follow, I will describe various additional objects,`- features andadvantages of my invention.

In-the accompanying drawings I have illus-'55 trated certain forms of myinvention, and in these drawings:

Fig. 1 isa diagrammatic view somewhat schematicv in character,illustrating the utility of my invention.

Fig. 2 is a vertical sectional view through one form c' the automaticvalve control mechanism of my invention.

Figs. 3, 4, 5, 6, and 7 are sectional views taken through Fig. 2 asindicated by the sectional lines and arrows bearing the numeralscorresponding to the diil'erent views. l

Fig. 8 is a vertical sectional view of schematic character .through asecond form of valve control means of my invention.

Figs. i?, 10, 11, 12, and 13 are sectional views oi.' Fig. 8 taken asindicated by the lines and arrows bearing corresponding numerals.

Fig. 14 is a sectional view showing another type of valve controlmechanism of my invention.

Fig. 15 is a vertical sectional view of schematic character showingstill another form of valve control mechanism which I have devised.

Referring to Fig. 1, the numeral II represents an oil well in which acasing or pipe I2 has been installed. At the lower end of this oil wellis a series of formations I4, I5, I6, I1', and I8. Adjacent theseformations is a screen pipe or strainer pipe 20 which is ordinarilysecured to the lower end of the casing I2.

In order to make la test of the well in accordance with the methoddisclosed in my Patent No. 1,786,196 referred to heretofore, it isnecessary to piace an electrolyte in the well from the bottom of thewell to approximately a level indicated by the line 22, which is abovethe periorations in the casing.

In order to so deposit an electrolyte in the wel I may use an apparatusfor delivering a charge of material in the well which may be in the formof any of the'diiferent types of apparatus illustrated in Figs. 2 to 14inclusive or may be in other forms incorporating the principles of myinvention which constitute the subject matter of the presentapplication. In Fig. 1 I have shown an apparatus 25 which represents myinvention. This apparatus is secured to the lower end of a cable 26 andis lowered into the well into a position approximately as shown inFig. 1. After the apparatus has reached this position the dischargevalve of the apparatus will be automatically opened and the contentsthereof will be thereupon discharged into the well and will ll thewell-to the level 22. It is obvious, of course, that if the space in thewell is quite large it may be necessary to deliver a number of chargesof electrolyte which is done by repeating the operation just described.After the electrolyte has been delivered into the well into the desiredposition the well may then be tested.

Having outlined the general procedure employed inv my invention when itis used for the purpose of delivering electrolyte into a well, I willnow describe the details of construction of different forms of theinvention incorporating the esthe shell 3l is a tubularmember or housing39. and this tubular member houses the Vvarious apparatus which isemployed to control the operation of the valve '34.

The valve 34 has a short stem 31 which fits into an upper section 39 ofa body, which body also includes a lower section 3l. The stem 3l isloosely supported in an opening 40 of the upper section by means o1' apin and slot arrangement 4I which includes the pins supported by theupper section 38 which t into slots formed in the stem 31. In thelowerpart of the cavity 46 is a spring 43 which forces the stem-31 andthe valve 34 upwardly. The body comprising the upper and lower sections39 and 39 is supported in a'xed position, as will be described later,and the spring 43 then constitutes a means for resiliently urging thevalve 34 against the seat 32. In order to provide for adjustment, whichmay be yrequired'in order to properly position the valve 34, thesections 39 and 39 are adjustably connected together by'means of athreaded pin 44 of the section 33 which is threadedly received in athreaded socket 45 ot the lower section 39.

The body which support the valve 34 is locked or retained in theposition shown in full lines in Fig. 2 by a latch means which I will nowdescribe. The lower part of the section 39 is provided in the form of adepending annular or cylindrical wall 56. This wall 56 has a pluralityof openings 5I formed in it which are preferably equally spaced aroundthe circumference oi' the wall 50. These openings 5I are ot such a sizeas to retain latch members in the form of balls 52. Formed in thehousing 36 is an annular channel 53 into which the balls 52 may extendwhen'the body is in the position shown in full lines in Fig. 2 and whenthe balls are held in the positions shown by means of a retaining member54. It will be seen that when the balls 52 are held in the positionsshown that they form a locking means between the annular wall 50 and thehousing 36, and therefore serve to lock the body in the position shownin i'ull lines in Fig. 2. When the body is so positioned the parts orsections 38 and 39 thereof are sov adjusted that the valve 34 engagesthe seat 32 and the spring 43 is compressed so that there is a resilientforce urging this valve against its seat.

The retaining means 54 includes a head 55 hav ing a cylindrical portion56 which is of such a size that when it is positioned adjacent the balls52 it holds the balls 52 so-that they are engaged in the channel 53.Above the cylindrical Wall 56 is a recess 5l. Above the recess 5l is aflange 58, and below the cylindrical wall 56 is a similar flange 59which linut the movement of the retaining means relative to the balls 52and the body. When the retaininng means is lowered relative to the valve34 of the body, as illustrated by dotted lines 60, the balls 52 are freeto move inwardly so that they are disengaged from the channel 53. rIlhisis effective in unlatching the body, and it will thereupon drop into adepressed position as indicated by dotted lines 62. It will be seen thatthis action lowers the valve 34 from closed position and allows thematerial in the chamber 3i to flow through the outlet passage 33 intothe upper end of the housing 36 and'out- Wardly into the well throughopenings 63 provided in the housing 36.

For the purpose of controlling the operation of ing means to movedownwardly relative tothe section 36 into the position indicated by thedotted lines 68. The mechanism which I provide vis constructed asfollows. Extended downwardly from the head 66 of the retaining means 54is a stem 66 having a nut 66 screwed on the lower end thereof which isprovided with left hand threads. This nut 66 has outwardly projectingarms "61 which extend intov vertical slots 68 formed in a release sleeve69. The upper ends of the slots 68 have horizontal portions 18 so as toprovide shoulders 1| upon which the arms 61 may rest, as shown in Fig.5, when the retaining means is to be held in the position shown in fulllines in Fig. 2. The nut 66 is threaded on the stem 68 so that it can beadjusted into a suitable position so that when the arms 61 rest on theshoulders 1| the cylindrical portion 56 of the head 64 will be adjacentthe balls 62, thus locking the body in place. The head of the retainingmeans is caused to move into the position indicated by dotted lines 60by rotating the release sleeve 69 in a clockwise direction when viewingFig. 5.

This brings the vertical portions of the slots 68' rest in the positionindicated by the dotted lines 62. *,As the entire assembly drops, theprojections 61 of the nut 66 move downwardly in the vertical slots 68.In order to provide a support for the parts in lowered position Iprovide a rubber bumper 14 which may be engaged by the lower end or thestern 65 when the parts drop as just explained.

For the purpose of rotating the release sleeve 59 I provide this releasesleeve with a downwardly projected shaft 15 which has a spring 16associated with it which is adapted to rotate the shaft 15 and therelease sleeve 69 in a clockwise direction when viewing Fig. 5.

For the purpose of locking the release sleeve in a position to hold thenut 66 in the position shown in Fig. 2, I provide a brake constructionincluding a toothed wheel 11 which is locked from rotation by means of aspring loaded pawl 18. The wheel 11 is mounted on a shaft 16 which is inturn connected to the shaft 15 through a gear and shaft arrangementindicated by the numeral 80. When the brake arrangement is in theposition shown in full lines in Fig. 2, the shaft 15 and release sleeve69 are locked in the positions shown. However, upon retracting the pawl18 into a position indicated by dotted lines 8|, the wheel 11 isreleased andthe spring may then rotate the shaft and release sleeve sothat the parts will be operated as pointed out heretofore. The releasesleeve 69 may be reset after actuation by any suitable means such, forexample, as a bevel gear 82 secured to the shaft 15 adapted to beengaged by a crank mechanism shown in dotted lines in Fig. 2, and whichis used only during` the resetting operation. The numeral 83 representsa gear secured to the inner end of a crank 84. The crank 84 may be heldin a suitable position to engage the gear 83 with the gear 82 by meansof a block 85a adapted to rit in an opening 85h provided in the housing36.

The pawl 18 is moved into disengaged position byv time control mechanismwhich I will now describe. Supported in the lower end of the housing 86is a solenoid consisting of a coil 86 and a core 66 adapted to be pulledinto the coil 86 when the coil is energized. This core 86 is connectedby a link 81 to the pawl 18 so that when the core is pulled downward thepawl is disengaged from the toothed wheel 11. For the purpose orenergizing the solenoid coil 86 I provide an electrical circuitincluding battery means 89 and. atime control switch 98. The timecontrol switch 60 has a stationary contact 9| and a movable contact 92which is operated by a suitable clockwork which is not `illustrated indetail because such mechanisms are well known in various industries. Themovable contact 92 may be set into any desired p ositlon relative toAthe stationary contact 8| by means of a setting knob 94 so that thetime before engagement of the movable contact and stationary contact maybe any desired period of time. The movable contact 92 is connected bymeans of a wire 66 to the housing 36fand is therefore grounded. The

stationary contact 9| is connected by a wire 91 to the battery 86, andthe battery 86 is connected to the solenoid coil 85 by means of aconductor t6. The other end of the solenoid coil 85 is connected byawire 99 to the housing 36, thus forming a complete circuit. It will beseen that when the movable contact 92 is moved into engagement with thestationary contact 9i that the solenoid coil 65 is energized, thuspulling the core 86 downward and thus moving the pawl 18 into theposition indicated by dotted lines 8|.

For simplification I have diagrammatically 1llustrated certainof theparts of my invention. It should be understood, however, that thevarious parts which are diagrammatically illustrated are either wellknown in the industry or may be readily made by any skilled mechanic. Ihave purposely left out certain details of construction of various partswhich may be employed to protect the mechanism of my invention. This hasbeen done since no invention is involved in such parts which I havepurposely left from the drawings, and it is believed that in this waythe construction is greatly simplied and therefore may be more readilyunderstood by those skilled in the art who, at theiry own volition, mayadd what other details of construction they desire.

It is believed that the full operation of the device just described isreadily understood. When the apparatus 25 is at the surface of theground the time control means 9E) is set so that the circuit will beclosed after a predetermined period of time, this period of time usuallybeing that required to lower the device into the well plus a few minutesto allow for any delay which might be occasioned. The apparatus is thenlowered into the well into a position shown in Fig. l and is supportedin the position shown in Fig. l at the time the contacts 9i and 62 areclosed. The charge of material in the chamber 3i is then discharged. Themanner in which the material is discharged, of course, depends` upon thedetails .of construction of the means for ejecting the material from theapparatus when the valve 34 is opened. In some types of apparatus it isnecessary to raise the apparatus slowly in order that the material inthe chamber 8| will be displaced by the well fluid entering the upperend of the chamber'l which is open.

The opening of the valve 34 is accomplished into dotted line position8|.

briefly point out in full as follows. When the contacts 9| and 82 areengaged the circuit is completed and the lsolenoid coil 85 energized.This depresses the core 86 and pulls the pawl 18 This releases the brakeon the shaft 15 and thus allows the spring 16 to rotate the shaft 15 andthe release sleeve 69 in clockwise direction. This first causes a.rotation of the sleeve relative to the nut 66 and causes the verticalportions of the slot 68 to be brought into alignment with the arms 61and then rotates the nut 66 on the stem 65to pull the retaining memberdown into position indicated by dotted lines 80. When the parts are inthis position the balls 52 may move inwardly, and when these balls 52move inwardly the body, including the upper and lower sections 38 and39, is released from the housing 36 and is then free to fall downwardlyinto the positions indicated by dotted lines 62 in Fig. 2. This lowersthe valve 34 and allows the charge. in the chamber 3| to flow downwardlythrough the outlet passage 33 and the opening 63 in the housing 36 intothe well.

The valve is reset into closed position as follows. The circuit to thesolenoid coil 85, if it has not already been broken, is broken so thatthe pawl will be returned to full line position in Fig. 2. The body isthen moved by inverting the device, for example to the position shown infull lines in Fig. 2 and at that time the retaining member is in theposition relative thereto, as shown bydotted lines 60, the balls beingin inward position. When the body is in this position the balls aresubstantially in alignment with the groove 53, and thereafter theretaining member is moved into the 'position shown in full lines byrotation of the release sleeve 69 in anti-clockwise direction so as tofirst bring the shoulders 1| into position facing the arms 61 and thenrotate the nut 66 on the stem 65 to move the head from its dotted lineposition to its full line position. This may be done by the use of thecranking mechanism illustrated by dotted lines in Fig. 2. It is possibleto rotate the shaft due to the factthat the toothed wheel 11 is providedwith teeth which are inclined and therefore may move past the engagementend of the pawl 18 in the direction required to rotate the shaft andrelease sleeve 68 to reset. If necessary, the upper section 38 may berotated relative to the lower section 39 in order to obtain a full andpositive resilient feeding of the valve 34. Furthermore, if desired, inorder to relieve any pressure on any oi the parts during resetting, theupper section 38 may be screwed rearwardly relative tothe lower section39. After the parts have all been set as described, the section 38 maythen be rotated relative to the section 39, thus raising the parts so asto bring the valve 34 into resilient engagement with the seat 32. Whenit is desired to lower the device into the well, the time means may bewound up and set as previously described so that the contacts will beclosed after a predetermined period of time.

In the form of my invention shownin Figs. 8 to 13 inclusive I illustratea closure valve |00 which engages a seat |0| in order to close an outletpassage |02 of the chamber |03. The valve |00 is supported by a body |05in a manner similar to that in which the valve 34 is supported, therebeing pins |06 supported by the body |05 which extend into grooves |01provided in the stem |08 of the Valve |00, and there also being acompression spring |03 urging the valve |00 in an upward direction.

The body |05 is locked in the position shown in Fig. 8 by a latch meanswhich consists of a plurality of latch members or balls I, the innerparts of which rest in an annular groove ||2 formed .in thebody |05. Theouter portions of the balls are in engagement with an internalcylindrical wall ||4 of a connector member ||5 which forms a part`of'the housing ||6 of the apparatus. For the purpose oi. retaining theballs or lock members in the positions shown in` full lines in Figs. 8and 10, I provide a retaining means which includes a retaining sleeveIIB. This retaining sleeve ||8 has openings ||8a through which the ballsextend. When it is desired to open the valve |00, this is done byrotating the retaining means in a clockwise direction. This moves theballs into such a position that they may move outwardly into recesses||9 which are formed in the connector member ||5 at an elevation whichis in the same horizontal plane as the annular groove ||2 of the body|05. When the balls move outwardly into the recesses ||9 they aredisengaged from the annular groove ||2, and therefore the body |05 ispermitted to move downwardly. This removes the valve |00 from its seatso that the material in the chamber |03 may flow through the outletpassage |02 and through openings |2| into the Well. The retaining meansis operated or moved into a released position by means of a coil spring|22, one end of which is secured to a wall |23 of the housing ||6, asillustrated at |24, and the other end |25 of the spring |22 is connectedto a stem or shaft |26 which extends downwardly from the retaining shell||8 and which has its lower end received by a bearing |21 of the wall|28 of the housing l I6. The retaining means, however, is ordinarilyrestrained from rotation by means of a brake which is illustrated bestin Figs. 8, l1, and 12. Secured to the upper portion of the shaft |26 isa brake drum |30 having a groove |3| formed in it. Received in thegroove |3| is a. brake band |32. One end of the brake band is pivotallysecured at |33 to the housing I6 and the other end of the brake band isconnected to an operating bar |34. The operating bar |34 is supported bythe walls of the connector 5 deilning an opening |35 through which theoperating bar |34 extends, and also by the supporting lug |36. Theoperating bar |34 extends through an opening |31 formed in the free endof the brake band |32, and the lower end of this operating bar iswidened as illustrated at |38. When the widened portion of the barextends through the opening |31 it will be seen that the free end of thebrake band is pulled away from the brake drum so that the brake band isapplied to the brake drum and the retaining-means is locked fromrotation. However, when the operating bar is moved downwardly so as tobring a narrow portion 40 thereof into a position within the opening |31the free end of the brake band |32 may move so as to release the brakes,and at this time the retaining means may be rotated by the action of thespring |22.

For the purpose of operating the operating bar I provide a tensionspring |42 at its lower end which exerts a downward force. The operatingbar, however, is retained in the position shown in Fig. 8 by means of aholding link |43 which, in this form of my invention, is a fusible linkwhich may be melted by the passage of an electric current through it,and when this occurs the spring uing H6.

|42 pulls the operating bar |84 downwardly so as to release the brakes.

For the purpose of melting the fusible link |49 I provide an electriccircuit including a source of energy in the form of a battery |46 whichis connected by a wire |41 to a movable contact |46.

The movable contact is adapted to be engaged, by

means which I will hereafter describe, with a stationary contact |49`which. is connected by means of a conductor |50 to the lower end ofthefusible link |43. The upper end of the fusible link|43 is connected by aconductor |61 to the housing ||6 which acts as a ground, the battery |46being also grounded to the housing. .When the movable contact |48 iscaused to engage the stationary contact |49 the circuit is completed andthe electricity will flow through the fusible link |43, thus melting it,and when the fusible link is melted the operating member |34 will bemoved downwardly as previously described, with the result that theretaining means is rotated so that the balls are moved into a positionthat they may move outwardly into the recesses H9.

For the purpose of closing the switch in the l circuit; that is, causingthe movable contact |46 to engage the stationary contact |49, I providetime control means which in this form of my invention is a hydraulicmeans. This hydraulic means is shown as comprising a chamber |60 whichis formed near the lower end of the hous- Wthin this chamber |66 is acylinder |6| having a piston |62 which is movable therein. AI'his piston|62 is engaged by a spring |63 which tends to move it in an upwarddirection. The piston |62 is provided with a passage |64, which passageis closed by a valve |65 which permits a flow of uid only in a directiontoward the chamber |66 provided by the cylinder |6|. The cylinder |6| isprovided with a small opening |66 which connects the chamber |66 withthe chamber |60. The chamber |60 is filled with a liquid, such as yoil,glycerine, etc. The piston |62 may be depressed by means of alongitudinal movable member |68 which is engageable at its lower endwith a flange |69 of the piston |62. When the piston is depressed theliquid in the chamber |66 will iiow through the passage |64 and into thechamber |66. The spring |63 then urges the piston |62 upwardly, thevalve |65 closing at this time. This Vforces the liquid through theopening |66. The rate of movement of the piston |62 in an upwarddirection depends upon the rate of flow of the liquid through theopening |60. When the piston-reaches its uppermost position the flange|69 is adapted to engage the movable contact |46 and to cause it toengage the stationary contact |49, and in this manner the circuit to thefusible link |43 is closed. It will be seen that when the piston isdepressed the length of time before the circuit to the fusible link willbe closed depends upon the distance that the piston |62 is depressed. Itis therefore possible to calibrate the upper end of the actuating rod|66 as indicated at |16, and in this way the length fusible link |49will be completed and this link will be melted. This will allow thespring |42 to pull the operating bar |34 downward. When this occurs thebrake band |321is released from the brake drum |30 and the spring|22,will then rotate the retaining means. The retaining means thenrotates the balls |so that they may fall into the recesses ||9. Thisdisengages the balls from the body |05 and the body may fall into alowered position, thus removing the valve from its seat.

In order to reset the device it is necessary to return the body to itsoriginal position and then to rotate the retaining means. The brake mustthen be set by returningthe operating member into the position indicatedin full lines in Fig. 8.

. This is done by raising the operating member and replacing the usedfusible link with a new link which holds the operating member in thedesired position. During this time, of course, the circuit to thefusible link must be broken. When it is desired to use the device in awell the piston is then moved downwardly by means oi the rod |68 to thedesired position so that the desired lapse of vtime before actuation maybe obtained.

In Fig. i4 I have illustrated a form of my invention which is not Whollyautomatic in its operation, but which may be operated from the surfaceof the ground. In this form of my inventon I do not use the hydraulictime means for closing a circuit including the fusible link. In place ofthis mechanism I use an electric circuit consisting of wires |60 and It!which may be extended to the suriace of' the ground through the cable 26which supports the apparatus 25. At the surface of the ground there is abattery |62 and a manually operable switch |83 included in the circuit.When the switch |66 is closed the electrical circuit is completed andthe fusible link |43 is'melted, thus allowing the spring |42 to depressthe operating bar |34, and in this manner the valve |06 may be removedfrom its seat. It will be seen that in this form of the invention thereis no time device to be set. The apparatus may be lowered into the wellinto any position desired, and whenever it is desired to deliver thematerial to the well it may be done by manually lclosing the switch |86.

In the form of my invention shown in Fig. l the electrical control meanswhich determines the position of the operating member |34, as shown inFig. S'has been eliminated and an operating member |34a has beenprovided which is directly actuated by the hydraulic time device.Therefore, in Fig. the lower end of the operating member |64a isprovided with anextenslon |66 which extends downwardly into the chamber|66. The lower end of the extension |96 is adapted to be engaged by theflange |66 of the piston |62 when this piston approaches its upperposition. When the extension |96 is engaged the operating member itflais moved upward and the brake band |62 is released in the same mannerthat it is released in the form of the invention shown in Figs. 8 to 13and in Fig. 14. all loi the parts operatel in the same manner asdescribed in connection with' Figs. 8 to 13 in- In the form of inventionshown in Fig. 15

clusive except that the electrical circuit has been 1. In an apparatusof the class described, for

delivering a charge of material into a well, and having a reservoir forholding the material and va valve operable to discharge the materialfrom said reservoir, the combination of: valve-opening means for openingsaid valve; and time means which may be set to actuate after a lapse oftime to actuate said valve-opening means.

2. In an apparatus of the class described, for delivering a charge ofmaterial into a well, and having a reservoir for holding the materialand a valve operable to discharge the material from said reservoir, thecombination oi': spring controlled valve-opening means for opening saidvalve; and time means whichmay be set to actuate after a lapse of timeto release the spring o! said valve-opening means in order to actuatesaid valve-opening means.

3. In an apparatus of the class described, for delivering a charge ofmaterial into a well, and having a reservoir for holding the materialand a valve operable to discharge the material from said reservoir, thecombination of: latch means whereby said valve may be latched in closedposition or permitted to assume an opened position; latch-retainingmeans whereby said latch means may be retained in latched or unlatchedposition; and time means which may be set to operate after apredetermined lapse oi' time to operate said latch-retaining means torelease said latch means.

4. In an apparatus of the class described, for delivering a charge ofmaterial into a well, and having'a reservoir for holding the materialand a valve operable to discharge the material from Said reservoir, thecombination of: latch means whereby said valve may be latched in closedposition or permitted to assume an opened position; latch-retainingmeans whereby said latch means may be retained in latched or unlatchedposition; and electrically operated releasing means comprising a timemeans which may be set to operate after a predetermined lapse of time tooperate said latch-retaining means to release said latch means.

5. In an apparatus o! the class described, for delivering a vcharge ofmaterial into a well, and having a reservoir for holding the materialand a valve operable to discharge the material from said reservoir, thecombination of: latch means whereby said valve may be latched in closedposition or permitted to assume an opened position; latch-retainingmeans whereby said latch means may be retained in latched or unlatchedposi- /tion.; and hydraulically operated time means which may be set tooperate after a predetermined lapse of time to operate saidlatchretaining means to release said latch means.

6. In an apparatus of the class described, for delivering a charge ofmaterial into a well, and having a reservoir i'or holding'the materialand a valve operable to discharge the material from said reservoir, thecombination of: a valve-supporting body which supports said valve inclosed or opened position; latch means for said valve supporting bodyfor holding said valve in closed position; retaining means for retainingsaid latch means in a latched position; release means for said retainingmeans which is operable to release said retaining means in order tounlatch said latch means and move said valve-supporting body into openedposition; and time-delay a valve operable to discharge the material fromsaid reservoir, the combination of: a valve-supporting body whichsupports said valve in closed or opened position; latch means for saidvalvesupporting body'for holding said valve in closed position;retaining means for retaining said latch means in a latched position;release` means for said retaining means which is operable to releasesaid retaining means in order to unlatch said latch means and move saidvalve-supporting body into opened position; a brake for restraining saidrelease means from operating; and time-delay means 'for releasing saidbrake.

8. In an apparatus of the class described, for delivering a charge ofmaterial into a well, and having a reservoir for holding the materialand a valve operable to discharge the material from said reservoir, thecombination oi: a valve-supporting body which supports said valve inclosed or opened position; latch means for said valvesupporting body forholding said valve in closed position; retaining means for retainingsaid latch means in a latched position; release means for said retainingmeans which is operable to release said retaining means in order tounlatch said latch means and enable movement of said valvesupportingbody into opened position; a brake for restraining said release meansfrom operating; and electrically operated releasing means comprisingtime-delay means for releasing said brake.

9. `In an apparatus of the class described, for delivering a charge ofmaterial into a well, and having a reservoir for holding the materialand a valve operable to discharge the material from said reservoir, thecombination of a `valve-supporting body which supports said valve inclosed or opened position; latch means for said valvesupporting body forholding said valve in closed position; retaining means for retainingsaid latch means in a latched position; release means for said retainingmeans which is operable to release said retaining means in order tounlatch said latch means and enable movement of said valvesupportingbody into opened position; a brake for restraining said release meansfrom operating; and brake release means for releasing said brake.

10. In an apparatus of the class described, for

delivering a charge of material into a well, the.

combination of: a reservoir for holding the material, said reservoirhaving a valve opening; a valve member for closing said opening; latchmeans for holding said valve member in such position that it will closesaid opening; power means operative to move said latch means out of itsholding position; and a time delay control means carried by saidapparatus in operative relation to said power means for governing theoperation of said power means so that the opening of said valve membermay be had at a desired time.

11. In an apparatus of the class described, for delivering a charge ofmaterial into a well, the combination of: a reservoir for said materialhaving an opening at the lower end thereof; a tubular member extendingdownwardly from the lower end of said reservoir; a valve member in theupper part of said tubular member adapted to be moved into a positionfor closing said valve opening of said reservoir; latch means adapted tobe moved outwardly from said valve member into engagement with saidtubular member to hold said valve member in raised position; a latchholding member having a latch holding position wherein it holds saidlatch means in engagement with said tubular member and a retractedposition wherein it releases .said latch opening of said reservoir;latch means adapted means, said latch holding member having a to bemoved outwardly from said valve member threaded part projectingdownwardly therefrom; into engagement with said tubular member to a nutmember engaging said 'threaded part; hold said valve member in raisedposition; a latch power means operative to rotate said nut memholdingmember having a latch holding position ber whereby to move said latchholding member wherein it holds said latch means in engagement fromlatch holding position to retracted position; with said tubular memberand a retracted posiand a releasing means for said power means optionwherein it releases said latch means, said erative to cause operation ofsaid power means latch holding member having athreade'd part prowherebysaid nut member will be rotated and saidI iecting downwardly therefrom;a nut member enlatch holding member will be retracted. gaging saidthreaded part; power means operative l2. In an apparatus oi the classdescribed, for to rotate said nut member whereby to move said deliveringa charge of material into a well, the latch holding member from latchholding position' combination of: a reservoir for said material toretracted position; and means operative to having an opening at thelower end thereof; a cause the operation of said power means, wherebytubular member extending downwardly from the said nut member will berotated and said latch lower end of said reservoir; a valve member inthe holding member will be moved into retracted posiupper part of saidtubular member adapted to tion. v be moved into a position for closingsaid valve GEORGE H. ENNIB.

